38o BACTERIA IN MILK 



speak of them as the "liquefying Giintheri" bacteria. In 1919 Orla- Jensen' described 

 them under the name of Streptococcus liquefaciens. Rogers and Dahlberg,^ in their 

 study of the streptococci of the udder, found eleven cultures of these liquefying 

 streptococci. There is much confusion regarding the identity of these acid-proteolytic 

 types, and it seems probable that much of the conflict in ideas regarding them is due 

 to this confusion. 



UDDER STREPTOCOCCI 



Investigators who have studied the udder flora are generally agreed that the or- 

 dinary sour-milk organism (Streptococcus lactis) does not occur in the udder. However, 

 pathogenic streptococci do frequently occur, and these are sometimes confused 

 with the saprophytic types that cause the normal souring of milk. On the basis of 

 the work of Avery and Cullen,^ who pointed out that the common mastitis strepto- 

 coccus gives a higher acidity in dextrose broth than the human, so-called Streptococcus 

 haemolyticus (S. pyogenes), and of the work of Ayers and Rupp,'' who pointed out that 

 the hemolytic bovine streptococcus was able to hydrolyze sodium hippurate while the 

 human streptococcus did not, it is generally believed that the bovine and human pyo- 

 genic streptococci should be recognized as distinct species. 



The name Streptococcus mastitidis Migula^ is perhaps most commonly applied to 

 the organism causing udder infections. This binomial is sometimes incorrectly at- 

 tributed to Guillebeau,* who used the descriptive trinomials Streptococcus mastitis 

 sporadicae and 5. mastitis contagiosae for two organisms that differed only as indicated 

 in the names, and that are today generally regarded as varieties of the same species. 

 Migula changed the spelling in making the binomial which he applied to the first of 

 Guillebeau's types. 



Lohnis' has stated that Guillebeau's organisms were gas-formers, but a careful 

 reading of the original paper does not indicate any characters other than those of 

 typical mastitis streptococci. On the other hand, Adametz^ in his 1893 and 1894 

 papers reports cultures of these organisms as causing gassy cheese and as producing 

 gas bubbles in milk cultures. In his 1893 paper Adametz does not refer to Kitt's use 

 of the trinomial 5'. agalactiae contagiosae 1893, though he quotes this name in his 

 1894 paper. The binomial 5. agalactiae appears to have been first used by Lehmann 

 and Neumann' where it is credited to Adametz. As this would appear to give the 

 binomial S. agalactiae priority, some writers prefer this name. If, however, Guillebeau 

 is regarded as having named two varieties of the same species, then the names S. 



' Orla- Jensen, S.: "The Lactic Acid Bacteria." Mem. Acad. Roy. Sc. el Lett. Danemark, Sect. Sc. 

 (8th ser.), s, 80. 1919. 



'Rogers, L. A., and Dahlberg, A. O.: /. Agric. Research, i, 491. 1914. 



3 Avery, O. T., and Cullen, E. G.: /. Exper. Med., 29, 215. 1919. 



■t Ayers, S. H., and Rupp, P.: J. Infect. Dis., 30, 388. 1922; Ayers, S. H., and Mudge, C. S.: 

 ibid., 31, 40. 1922. 



5 Migula, W.: System der Bakterien, 2, p. 19. Jena, 1900. 



''Guillebeau, A.: Landw. Jahrb. d. Schweiz, 4, 27. 1892; Centralbl. f. Baklcriol., 12, loi. 1892. 



'Lohnis, F.: Ilandb. d. landw. Baktcriol., p. 198. BerUn. 1910. 



8 Adametz, L.: J.f. Landiv., 42, 231. 1894. Milchzeitung, 22, 235-40. 1893. 



'Lehmann, K. B., and Neumann, R. O.: Bakleriologisclie Diagnostik. (ist ed.)- Munich, 1S96. 



